Xfinity Stream on Firestick - activate error - XFinity

I have installed the Xfinity Stream app on my new Amazon Firestick 4K per several posts and videos. It seems to install correctly, but when I go to use it, I get an error “Unknown Protocol”. At the bottom of the screen was a reference to “xtvauth://activate/?responseCode=200&activationCode=...{long key}...paternId=comcast>

I tried uninstalling and reinstalling the app on the Firestick - no impact.

I tried rebooting the Firestick several times - no impact.

Appreciate any feedback on what the issue might be and how to correct.

This question, "Xfinity Stream on Firestick - activate error," is about XFinity-Comcast TV Television Apps.

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